Related papers: High energy protons from PKS 1333-33
The cosmic ray source spectrum produced by AGN (Active Galactic Nucleus) jets is calculated. A distinctive feature of these calculations is the account for the jet distribution on kinetic energy. The expected cosmic ray spectrum at the…
Nearby radio galaxies are among the most promising candidates for the acceleration of ultra-high-energy cosmic rays (UHECRs). In this work, we develop a physically motivated, source-resolved framework to quantify the contribution of the…
In the last years, Active Galactic Nuclei (AGN) have become more popular than ever. The possibility of using them to produce feedback effects that would help solving some of the still open questions connected to the hierarchical scenario of…
The nearby radio galaxy 3C293 is one of a small group of objects where extreme outflows of neutral hydrogen have been detected. However, due to the limited spatial resolution of previous observations, the exact location of the outflow was…
A shock-accelerated particle flux \propto p^-s, where p is the particle momentum, follows from simple theoretical considerations of cosmic-ray acceleration at nonrelativistic shocks followed by rigidity-dependent escape into the Galactic…
The antiproton-to-proton ratio in the cosmic-ray spectrum is a sensitive probe of new physics. Using recent measurements of the cosmic-ray antiproton and proton fluxes in the energy range of 1-1000 GeV, we study the contribution to the…
Radio and $\gamma$-ray measurements of large lobes of several radio galaxies provide adequate basis for determining whether emission in these widely separated spectral regions is largely by energetic electrons. This is very much of interest…
I review observational properties of low power radio loud AGN. High resolution VLBI observations allow the estimate of the jet velocity and orientation with respect to the line of sight and the determination of the Doppler factor. These…
Observations of the FR I radio galaxy Centaurus A in radio, X-ray and gamma-ray bands provide evidence for lepton acceleration up to several TeV and clues about hadron acceleration to tens of EeV. Synthesising the available observational…
We propose the model of the global structure of the electromagnetic fields in the Fermi bubbles (FBs), which makes possible the proton regular acceleration up to ultra-high energies. The poloidal and the toroidal magnetic fields, as well as…
Super-Eddington accretion onto stellar-mass compact objects powers fast outflows in ultra-luminous X-ray sources (ULXs). Such outflows, which can reach mildly relativistic velocities, are often observed forming bubble structures. Wind…
We analyzed near-infrared data of the nearby galaxy IC5063 taken with the Very Large Telescope SINFONI instrument. IC5063 is an elliptical galaxy that has a radio jet nearly aligned with the major axis of a gas disk in its center. The data…
A fraction of merging galaxy clusters host diffuse radio emission in their central region, termed as a giant radio halo (GRH). The most promising mechanism of GRHs is the re-acceleration of non-thermal electrons and positrons by…
Protons of energies up to 10**20 eV can be subject to significant deflection and energy dependent time delay in lage scale extragalactic or halo magnetic fields of strengths comparable to current upper limits. By performing 3-dimensional…
Shock waves associated with shell type supernova remnants are considered to be possible sites of cosmic ray acceleration. Since shocks are capable of accelerating electrons in addition to protons one anticipates both species to contribute…
We present the general properties of the Active Galactic Nuclei (AGNs) and discuss the origin and structure of jets that are associated to a fraction of these objects. We then we address the problems of particle acceleration at highly…
We discuss the most recent developments in our understanding of the acceleration and propagation of cosmic rays up to the highest energies. In particular we specialize our discussion to three issues: 1) developments in the theory of…
Diffuse background of high energy neutrinos arising from interactions of cosmic ray protons with far infrared radiation background in extragalactic space is calculated. It is assumed that cosmic ray spectrum at superhigh energies has…
We present ATCA radio observations of the giant radio galaxy J0116-473 at 12 and 22 cm wavelengths in total intensity and polarization. The images clearly reveal a bright inner-double structure within more extended edge-brightened lobe…
Active Galactic Nuclei are considered as possible sites of cosmic ray acceleration and some of them have been observed as high energy gamma ray emitters (Blazars). There naturally comes an appealing idea that the acceleration of the highest…